Cadillac Seville / Cadillac Eldorado Forum Discussion, Questions about the rare 2004 SLS and Northstar in Past Cadillac Vehicle Discussion; I'm in the market for a used car again.
I heard that 2004 and later LD8 275hp Northstars received a ...

Questions about the rare 2004 SLS and Northstar

I'm in the market for a used car again.

I heard that 2004 and later LD8 275hp Northstars received a coarser thread pitch for the head bolts to prevent head gasket failure. I know LD8 Devilles got this change for the 2004+ model years. So did the LD8 2004 Seville SLS receive the same improvements?

My understanding is also that the 2004 SLS also got the standard body colored trim like the STS but did not get CVRSS or F55 Magneride. Is this true as well?

It would seem, if the above is all true, that the most dependable Seville to buy is the 2004 SLS. Can anyone confirm?

Re: Questions about the rare 2004 Seville SLS and Northstar

Jesda, The last STS (K body) rolled off the line in June of 03, and STS was the only Seville to get F55 Magnetic Ride Control so it's pretty safe to say that the last gasp SLS didn't get it - and the last SLS was built in 12/03, 5 months into the 2004 model year. After that I think the production lines were rebuilt to handle the Sigma "STS" - a VIN check would tell if the later "STS" came from Hamtramck. As far as head bolt thread/length, I'll go with Chris - the whole new FWD Northstar came in for the later "DTS", so that's anyone's guess...........

Someone who regularly overhauls these Northstars - Jake Wiebe, Tim Carroll, or Joe at Midwest - would know for sure.

FWIW, my 2002.5 STS was bought by me on 11/21/05 and so far, at 63,500 miles, the only costs have been gas, oil, filters, tires, brakes, and a complete fluids exchange by Fitzgerald Cadillac. One CKP was replaced under warranty. Otherwise, the car is dead nuts reliable. Oh.........the driver's seat heater crapped out last January. WhoopDeeDooo !

Re: Questions about the rare 2004 Seville SLS and Northstar

When I went to replace my wife's 1993 STS I also went with a 2002 SLS because of the passive supension components. Basically because of the long term maintenance costs being cheaper and also because of the slightly better gas mileage. We bought the 2002 SLS with 23,000 miles on it in October of 2007, in the five years since the only expense besides a new set of Michelins and regular maintenance have been a new pair of CKP's and a new front wheel bearing module. The car now has 63,000 miles on it. To be honest at this point I don't miss the difference between the STS and SLS. If long term, high mileage is the kind of use the car will be getting I'd definitely recommend the SLS (as long as it has the STS trim).